Abstract
BACKGROUND: Lower leisure-time physical activity (LTPA) and higher body mass index (BMI) are independently associated with risk of heart failure (HF). However, it is unclear if this relationship is consistent for both heart failure with preserved ejection fraction (HFpEF) and heart failure with reduced ejection fraction (HFrEF). OBJECTIVES: This study sought to quantify dose-response associations between LTPA, BMI, and the risk of different HF subtypes. METHODS: Individual-level data from 3 cohort studies (WHI [Women's Health Initiative], MESA [Multi-Ethnic Study of Atherosclerosis], and CHS [Cardiovascular Health Study]) were pooled and participants were stratified into guideline-recommended categories of LTPA and BMI. Associations between LTPA, BMI, and risk of overall HF, HFpEF (ejection fraction ≥45%), and HFrEF (ejection fraction <45%) were assessed by using multivariable adjusted Cox models and restricted cubic splines. RESULTS: The study included 51,451 participants with 3,180 HF events (1,252 HFpEF, 914 HFrEF, and 1,014 unclassified HF). In the adjusted analysis, there was a dose-dependent association between higher LTPA levels, lower BMI, and overall HF risk. Among HF subtypes, LTPA in any dose range was not associated with HFrEF risk. In contrast, lower levels of LTPA (<500 MET-min/week) were not associated with HFpEF risk, and dose-dependent associations with lower HFpEF risk were observed at higher levels. Compared with no LTPA, higher than twice the guideline-recommended minimum LTPA levels (>1,000 MET-min/week) were associated with an 19% lower risk of HFpEF (hazard ratio: 0.81; 95% confidence interval: 0.68 to 0.97). The dose-response relationship for BMI with HFpEF risk was also more consistent than with HFrEF risk, such that increasing BMI above the normal range (≥25 kg/m(2)) was associated with a greater increase in risk of HFpEF than HFrEF. CONCLUSIONS: Our study findings show strong, dose-dependent associations between LTPA levels, BMI, and risk of overall HF. Among HF subtypes, higher LTPA levels and lower BMI were more consistently associated with lower risk of HFpEF compared with HFrEF.